There is need for a practical, reliable and definitive test for the detection of chronic lead poisoning. We propose to determine whether a computer/scanner system for rapid screening of radiographs can effectively detect this condition. We propose further to investigate the hypothesis that lead stored in bone and released into the blood stream over a period of time can cause repeated recurrence of symptoms after exterior lead sources have been eliminated; in this phase of the study we propose to test the usefulness of the computer/scanner system for quantitatively measuring the extraction of lead from bone as differentiated from the extraction of lead from the blood stream. We intend to analyze a substantial quantity of radiographs of known lead poisoning cases by: (1) measurement of radiographic bone size, weight and density combined with comparison of findings to normal values; and (2) line-scanning of selected bones to establish a mineral distribution profile which may pinpoint dense deposits in growing ends of bones (so-called "lead lines"). If, as our pilot studies lead us to believe, definitive patterns emerge, we will test the screening capability of the system in a blind study which will include 150 lead poisoning patients and 150 normal subjects. We will, in addition, analyze the bone densities of 150 suspected lead poisoning cases who present a range of blood lead levels and follow the progress of 50 patients receiving treatment to determine the relationship between lead stored in bone and blood lead levels and to establish any patterns of mobilization following chelation.